The current invention relates to the field of passive cleaning devices for swimming pools, and particularly to an improved, stationary apparatus for collecting floating debris in swimming pools having a circulatory current therein.
Cleaning a swimming pool of debris is a common problem among pool owners. Such debris may enter swimming pools from many different sources. Wind and rain carry falling leaves, insects, dust, twigs and other objects onto the surface of the water in the pool where it may float for a period of time before sinking to the bottom. It is desirable to remove such debris before it becomes waterlogged and sinks to the bottom of the swimming pool, since the cleaning of bottom-resident debris by means of vacuum devices is labor intensive and costly.
The prior art is replete with devices for skimming floating debris. Most such devices have a frame and netting construction. Handheld devices rely on human action to sweep the skimmer along the pool's surface to entrap floating debris, while passive devices are fixed along the edge of the pool and rely upon circular around the perimeter of the pool which are produced by the water jets of the pool filtration pump. These currents may be further enhanced by the Coriolis effect, which in the Northern Hemisphere is manifested by a tendency for objects moving in a straight line to move right, or clockwise. These passive devices are partially submerged in a pool with the inlet or water intake leading to a collection area. The inlet faces into the circulating water current, which flows through the device and exits through an outlet. Debris is caught in the netting at the collection area, which is generally colocated with the outlet.
For example, U.S. Pat. No. 5,849,184 discloses a device having an elongated inlet portion and a similarly elongated collection portion extending the width of the device, the inlet portion being positioned perpendicular to the flow of water.
U.S. Pat. No. 4,089,074 discloses a triangular-shaped frame supporting a net with the inlet side of the triangle perpendicular to the flow of water and a collection area at the apex opposing the inlet side. The current flows through the inlet portion and out through the collection portion, which collects debris in the main current flow.
U.S. Pat. No. 5,264,122 discloses a floating stationary pool cleaner having a collection portion and an inlet portion but with integral water jets directing the floating debris into the inlet portion. As with U.S. Pat. No. 4,089,074, the current flows through the inlet portion and out through the collection portion, which collects debris in the main current flow.
U.S. Pat. No. 5,173,181 discloses an apparatus for positioning the detachable strainer from a manual pool scoop in an orientation perpendicular to the flow of the water in the pool, by means of a bracket attached to the pool's side. It has an inlet and collection portion as well.
U.S. Pat. No. 5,279,728 discloses a basket or collection portion to receive debris from the circular flow in a pool. A tube and nozzle arrangement directs a forced flow of water through the basket portion, thus, presumably creating a circular current within the pool.
U.S. Pat. No. 5,288,414 discloses another supporting device for a collection portion, in which the collection portion for skimming debris is supported by a support member attached to the side of the pool and a float around the neck of the support member.
U.S. Pat. No. 5,759,388 discloses yet another stationary skimming device floating on the surface of the pool, having an inlet portion perpendicular to the flow of water and a collection portion at the opposing end, similar to that of U.S. Pat. No. 4,089,074.
U.S. Pat. No. 5,911,878 discloses another passive pool skimmer with an elongated inlet portion and an outlet portion of roughly the same extent. It is non-rigidly secured to the side of the pool and is configured so that it does not present a hazard to swimmers.
However, all such pool skimmers share the same problem, namely, that debris has a tendency to float out of the skimmer collection area when a certain amount of debris is collected; the debris can thus reenter the swimming pool where it either sinks to the bottom or else is collected again by the skimmer. This phenomenon has been observed to a greater or lesser extent in all such pool skimmers.
This observed phenomenon is believed to be caused by the following actions. The general circular pool current brings debris into the skimmer collection area and flows on through the netting collecting the debris. The current as it flows through the skimmer tends to keep the debris against the netting comprising the outlet portion. As the debris accumulates against the netting, the current flowing through the skimmer from its inlet to its outlet portions is reduced and the force keeping the debris against the netting of the outlet portion is lessened. As the current through the skimmer becomes weaker, the force keeping the debris against the netting of the outlet portion is weakened, thus allowing the trapped debris to float forward towards the inlet portion against the current. Eventually the debris escapes the skimmer and is reintroduced into the swimming pool. It is also observed that the netting itself presents resistance to the swimming pool current; this resistance can be increased by using a finer mesh netting or some other permeable material, or decreased by using a coarser mesh. The accumulation of debris at the outlet portion forces pool owners to frequently clean the outlet/collection area in order to keep the circulatory pool current path clear and unimpeded. If the debris could be removed from the collection area before it could accumulate and impede water flow out the outlet area, then the skimmer could operate more efficiently for longer periods.
In prior art, cleaning the pool skimmer is an tedious task. Most devices use a form of netting as the filter means. The advantage of using a netting for snagging and holding debris also serves as a disadvantage in the cleaning process. Removing the debris from the netting while the netting is attached to the device often is awkward and difficult.
Thus, it can be seen that there is a need for a pool skimmer which effectively traps increased amounts of debris without allowing the trapped debris to be reintroduced into the swimming pool after capture. The skimmer should also be easily cleaned.